The Kennel Club reports that these dams suffer dystocia more often
from uterine inertia than a physical blockage, while some other less prevalent cases were due to vaginitis, pyometra, infertility, and agalactia.
According to The Kennel Club, the Pekingese tend to suffer
from dystocia with most of the litters experiencing more bouts of
uterine inertia as opposed to a physical blockage.